Maine enacts shellfish closures along most of coast to test for red tide

ELLSWORTH, Maine — In an effort to prioritize the state’s red tide testing program, Maine fishery officials have prohibited harvesting mussels and European oysters along most of the coast between New Hampshire and Canada.

The widespread closure does not reflect a large outbreak of red tide, also known as paralytic shellfish poisoning, according to Kohl Kanwit, director of public health for Maine Department of Marine Resources. Kanwit said Friday evening the state has closed most of the coast to mussel and European oyster harvesting so it can focus its efforts on testing clams.

There is no ban on the harvesting of American oysters, which are the predominant species cultivated by oyster aquaculture growers in Maine, she said.

Kanwit said there are several reasons for the change in the testing program. Widespread outbreaks of red tide along Maine’s coast in 2008 resulted in the state receiving federal relief funds to test for the naturally occurring toxin. That money ran out last year, she said, which has forced DMR to reconsider how to allocate its red tide testing funds.

Maine’s annual softshell clam harvest is several times more valuable than its mussel landings — $16.9 million versus $2.3 million in 2013 — so DMR decided it would be more cost effective to focus the department’s limited testing resources on clams, she said. Because red tide contamination fluctuates more wildly with mussels than with other species, testing mussels can use up more time and energy than testing other species, she added.

Kanwit said the department plans to test all commercially grown mussels, so aquaculture firms can continue operating as usual. Some areas, such as most of inner Penobscot Bay, remain open to mussel harvesting, so people who harvest wild mussels commercially or recreationally will have places they can go.

There are closures for other shellfish species. West of Stonington, areas that are closed to mussel and European oyster harvesting are closed to the harvesting of surf or hen clams and carnivorous snails. She said all the closures for mussels, European oysters, surf or hen clams and carnivorous snails are expected to remain in effect through the end of August.

Along most of the southwest coast, from the Piscataqua River to West Cundy Point in Harpswell, clam harvesting has been banned because of a routine seasonal outbreak of red tide, Kanwit said. Some productive areas in the region remain open to clam harvesting and are being regularly tested so commercial clammers can continue working, she added.

“It’s impacting very, very little,” Kanwit said of the economic impact of the clam closure.